English

Disconnectedness properties of Hyperspaces

General Topology 2018-09-19 v1

Abstract

Let XX be a Hausdorff space and let H\mathcal{H} be one of the hyperspaces CL(X)CL(X), K(X)\mathcal{K}(X), F(X)\mathcal{F}(X) or Fn(X)\mathcal{F}_n(X) (nn a positive integer) with the Vietoris topology. We study the following disconnectedness properties for H\mathcal{H}: extremal disconnectedness, being a FF^\prime-space, PP-space or weak PP-space and hereditary disconnectedness. Our main result states: if XX is Hausdorff and FXF\subset X is a closed subset such that (a)(a) both FF and XFX-F are totally disconnected, (b)(b) the quotient X/FX/F is hereditarily disconnected, then K(X)\mathcal{K}(X) is hereditarily disconnected. We also show an example proving that this result cannot be reversed.

Keywords

Cite

@article{arxiv.1809.06807,
  title  = {Disconnectedness properties of Hyperspaces},
  author = {Rodrigo Hernández-Gutiérrez and Angel Tamariz-Mascarúa},
  journal= {arXiv preprint arXiv:1809.06807},
  year   = {2018}
}
R2 v1 2026-06-23T04:10:23.135Z